Mitsubishi Electric PUMY-P36NKMU3 Technical & Service Manual page 109

8-8. HOW TO CHECK THE COMPONENTS
<Thermistor feature chart>
Low temperature thermistors
• Thermistor <Hic pipe> (TH2)
• Thermistor <Outdoor liquid pipe> (TH3)
• Thermistor <Suction pipe> (TH6)
• Thermistor <Ambient> (TH7)
Thermistor R0 = 15 k" ± 3 %
B constant = 3480 ± 1 %
1
R =15exp{3480( –
t
273+t
32°F [0:] 15 k"
50°F [10:] 9.6 k"
68°F [20:] 6.3 k"
77°F [25:] 5.2 k"
High temperature thermistor
• Thermistor <Compressor> (TH4)
Thermistor R120 = 7.465 k" ± 2 %
B constant = 4057 ± 2 %
1
R =7.465exp{4057(
t
273+t
68°F [20:] 250 k"
86°F [30:] 160 k"
104°F [40:] 104 k"
122°F [50:] 70 k"
140°F [60:] 48 k"
OCH733
1
)}
273
86°F [30:] 4.3 k"
104°F [40:] 3.0 k"
1
– )}
393
158°F [70:]
176°F [80:]
194°F [90:]
212°F [100:]
230°F [110:]
50
40
30
20
10
0
500
400
300
200
34 k"
24 k"
17.5 k"
100
13.0 k"
9.8 k"
0
109
−4 −14 32 50 68 86 104122
−20 −10 0 10 20 30 40 50
Temperature (ºF)
Temperature (:)
122 167 212 248
77
50 75 100 120
25
Temperature (ºF)
Temperature (:)